I broke up with my girlfriend due to lack of trust

I had this girl that I know in my department, we were friends and I like her but never said so, one night in the party she hung out with a guy and they kissed at my front, my Coursemate’s laughed at me because they felt we were dating and she did that to me…months later, I got a girlfriend in my department, I really love her and she also do same, tho I never kept enemity with my old female friend, the way we do hang out reduced drastically and I promised myself not to go back to her.. of my girlfriend sees me with her just talking (not at close distance) she’ll get angry. She’s asking that I should block her totally amd stop talking to her even though she never wronged her